Double concave lenses are used to disperse light. They can make telescopes, suitable for a variety of applications, including scientific experiments, photography, and optical instruments.SpecificationColor: TransparentMaterial: GlassFocal Length: 75mmOverall Size: 30 x 4mm / 1.18 x 0.16 inch(OD*H)Packing List: 3 x Glass LenAdvantageMade of quality glass that is durable, scratch resistant, and provides excellent optical performance. Round edges have been polished, it is not easy to hurt your hand when you assemble it.Designed with a double concave shape that let the light diffuse and produces virtual images.The lens is accurately measured and has consistent curvature, ensuring consistent performance and results.InstructionPlace the concave side of the lens facing the object from which you want to disperse the light.
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